Air brake systems have been in use on heavy vehicles for many years. To protect air brake systems from dirt and debris getting to vital components, filters are typically used throughout the system. Filter mesh screens may be used at the coupling location of a semi-truck trailer on the two air line hoses that run to the truck cab. These two air lines supply a constant air supply on one side for emergency system functions and a supply of air pressure to the brake function when the driver applies the brake pedal. Both of these filters can become easily clogged with dirt and debris when a truck/trailer combination is used in a fleet of other trailers. In some instances these filters must be cleaned on a daily basis to ensure proper brake function of the trailer. Improved air filter configurations are desired.